LIFE SCIENCE

Detailed explanation-1: -Structures that have no apparent function and appear to be residual parts from a past ancestor are called vestigial structures. Examples of vestigial structures include the human appendix, the pelvic bone of a snake, and the wings of flightless birds.

Detailed explanation-2: -Vestigial structures are inherited from ancestors, but have lost much or all of their original function.

Detailed explanation-3: -These structures, which are often reduced in size, are known as vestigial structures. Examples of vestigial structures include the tailbone of humans (a vestigial tail), the hind leg bones of whales, and the underdeveloped legs found in some snakes (see picture at right).

Detailed explanation-4: -Structures inherited from a common ancestor are called homologous structures, or homologies.

Detailed explanation-5: -Further evidence for the idea of evolution is the existence of vestigial structures. These vestiges are structures that are genetically determined but have lost some or all of their original function from the ancestral species.